diff --git a/types/upng-js/index.d.ts b/types/upng-js/index.d.ts
new file mode 100644
index 0000000000..a6b31f54a6
--- /dev/null
+++ b/types/upng-js/index.d.ts
@@ -0,0 +1,20 @@
+// Type definitions for upng-js 2.1
+// Project: https://github.com/photopea/UPNG.js
+// Definitions by: York Yao <https://github.com/plantain-00>
+// Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
+
+export function decode(buff: ArrayBuffer): PngData;
+
+export function encode(bufs: ArrayBuffer, width: number, height: number, ps?: number, dels?: any[]): ArrayBuffer;
+
+export function toRGBA8(out: PngData): ArrayBuffer;
+
+export interface PngData {
+    width: number;
+    height: number;
+    depth: number;
+    ctype: any;
+    frames: any;
+    tabs: any;
+    data: ArrayBuffer;
+}
diff --git a/types/upng-js/tsconfig.json b/types/upng-js/tsconfig.json
new file mode 100644
index 0000000000..e6499c55f2
--- /dev/null
+++ b/types/upng-js/tsconfig.json
@@ -0,0 +1,23 @@
+{
+    "compilerOptions": {
+        "module": "commonjs",
+        "lib": [
+            "es6"
+        ],
+        "noImplicitAny": true,
+        "noImplicitThis": true,
+        "strictNullChecks": true,
+        "baseUrl": "../",
+        "typeRoots": [
+            "../"
+        ],
+        "types": [],
+        "noEmit": true,
+        "forceConsistentCasingInFileNames": true,
+        "strictFunctionTypes": true
+    },
+    "files": [
+        "index.d.ts",
+        "upng-js-tests.ts"
+    ]
+}
diff --git a/types/upng-js/tslint.json b/types/upng-js/tslint.json
new file mode 100644
index 0000000000..3db14f85ea
--- /dev/null
+++ b/types/upng-js/tslint.json
@@ -0,0 +1 @@
+{ "extends": "dtslint/dt.json" }
diff --git a/types/upng-js/upng-js-tests.ts b/types/upng-js/upng-js-tests.ts
new file mode 100644
index 0000000000..4b0823baa0
--- /dev/null
+++ b/types/upng-js/upng-js-tests.ts
@@ -0,0 +1,5 @@
+import * as UPNG from 'upng-js';
+
+declare const buff: ArrayBuffer;
+const img = UPNG.decode(buff);
+const rgba = UPNG.toRGBA8(img);